The present invention relates to a joint surveillance target attack radar system, hereinafter referred to as JSTARS. More particularly, the invention relates to an airborne segment of JSTARS and the computer processors thereof.
JSTARS is designed to detect, track and classify formations of vehicles as they move through the "corps area" towards the front line. The "corps area" is the area in which such forces are most vulnerable to attack by aircraft or missiles such as the Army Tactical Missile System (ATACMS), and is usually considered to extend some 150-175 km behind the front line. In order to have a reasonable chance of survival, however, any airborne radar system has to remain well behind the friendly line. Thus, JSTARS must spot individual moving vehicles at very long ranges.
This is done with the assistance of a large antenna, with high average power and high peak power. The size of the antenna is approximately 24 ft long by 2 ft deep. It is mechanically scanned in elevation, can swivel to look on either side of the aircraft and is scanned electronically in azimuth. The system operates in X-band, providing the necessary resolution and range.
The sheer size of the antenna is in itself significant in the detection of low-speed targets. Doppler shifts in the ground clutter, due to the movement of the platform, are inevitable and can blur the Doppler shifts from slow-moving targets. The size of the antenna is important because, if the antenna is larger, the beam is narrower. The Doppler shifts in the ground return are spread over a smaller velocity range.
The basic moving target indication (MTI) mode used in JSTARS was developed in the late 1970s, and also takes advantage of the size of the antenna. In a simplified example of the process, two side-looking antennas could be mounted on the same aircraft, separated longitudinally. The second would pulse slightly later than the other, but at precisely the same point in space. Static targets would give identical returns to each pulse, but a moving target would be different. Subtracting the returns would reveal the "mover" through the main-lobe clutter.
This principle is used in JSTARS, but in a much refined manner. The process is carried out synthetically by the programmable signal processor, and the antenna acts as three sub-arrays rather than two. The signal subtraction is done twice, once between the front and center sub-arrays and once between the center and rear sub-arrays, so there are two target signals. The difference in phase of arrival between these signals provides a very accurate indication of the target's bearing in azimuth. The system's computers compare the result with the on-board terrain database and the target's range, and calculate the target's exact three-dimensional position.
JSTARS is not a synthetic aperture radar (SAR) as such. SAR relies on the movement of the platform to provide a very large-aperture, very high-resolution image of static objects on the ground. SAR and MTI are complementary: SAR cannot see targets that move and MTI cannot see them when they stop. JSTARS does have a SAR mode, which is used in precisely that event. If the operator sees a group of targets vanish from MTI, he can activate SAR and confirm that they have stopped. SAR can also be used for strike damage assessment. Targets that do not move after an attack may have been hit.
Although the operational implementation of Pave Mover technology was controversial from the start, unlike a system reliant on a large ground station, JSTARS can be operational anywhere in the world in a matter of hours, playing the same non-threatening, crisis-management role as the E-3.
There are 17 operation and control station consoles. This reflects the ability of the system to supply data and the number of uses to which JSTARS information can be put. Each operator console has a screen, trackball and reconfigurable, touch-sensitive keypads.
Similar terminals are installed in mobile ground stations. All moving-target information is broadcast through the surveillance and control data link and the operators can request other information, such as SAR imagery, which is compressed before transmission.
The 17 operators can each concentrate on a different target area. Each can command a wide range of functions: wide area search, covering the entire area in view; sector search, in which the radar searches a particular area or a selected road; attack planning or control, in which a target area is viewed at higher resolution; target classification; and SAR/fixed-target modes, in which the radar can be set to display only targets above a given size.
As the operators command the radar to do different tasks, they share time on the radar. Each task is assigned a priority and a "revisit interval", as the radar completes one task, the control software sorts through the tasks that are due to be revisited and instructs the radar to do the job that has the highest priority. With electronic scanning in azimuth and extremely rapid scanning in elevation, the radar is highly agile.
ACD--Aircraft Change Directive PA0 ACP--Advanced Computer Program PA0 ACSN--Advanced Change Study Notice PA0 ADT--Air Data Terminal (of the SCDL) PA0 APL--Acceptable Performance Level PA0 ATP--Acceptance Test Plan (or Procedure) PA0 ATR--Air Transport Rack PA0 BIT--Built-in-Test PA0 CCC--Change Configuration Control PA0 CDC--Control Data Corporation PA0 CDP--Central Data Processor PA0 CDR--Critical Design Review PA0 CDRL--Contracts Data Requirements List PA0 CFE--Contractor Furnished Equipment PA0 CG--Center of Gravity PA0 CMOS--Cadmium Metal Oxide Semiconductor PA0 COTS--Commercial Off-the-Shelf PA0 CPCI--Computer Program Configuration Item PA0 CPI--Computer Program Item PA0 CPU--Central Processing Unit PA0 CSE--Common Support Equipment PA0 CWS--Communications Work Station PA0 DARTS--Data Analysis and Reduction Test Software PA0 DBCP--Data Bus Control Processing PA0 DCAS--Defense Contracting Auditing Service PA0 DCL--Digital Command Language PA0 DCP--Digital Control Program PA0 DDB--Digital Data Bus (a MIL-STD-1553B bus) PA0 DDED--Design Data Element Dictionary PA0 DDP--Digital Display Processor PA0 DEC--Digital Equipment Corporation PA0 DECNET--DEC Network (A Trademark Product of Digital Equipment Corp.) PA0 DED--Data Element Dictionary PA0 DFS--Data Formatting System PA0 DIB--Digital Interface Buffer PA0 DITMCO--Continuity Tester ("Drive-In Theater Maintenance Co.") PA0 DMA--Direct Memory Access PA0 DRP--Data Reduction Program PA0 DTM--DEC/Test Manager PA0 ECS--Environmental Control System PA0 EEPROM--Electrically Erasable Programmable Read Only Memory PA0 EMC--Electromagnetic Compatibility PA0 EMI--Electromagnetic Interference PA0 EO--Engineering Order PA0 ESMC--Embedded Single Board Module Computer PA0 ESS--Environmental Stress Screening PA0 EXP--Raytheon MVCF-860 Computer Expansion Chassis PA0 FCA--Functional Configuration Audit PA0 FFF--Form, Fit and Function PA0 FMECA--Failure Mode Effects and Criticality Analysis PA0 FQT--Formal Qualification Test PA0 FRACAS--Failure Reporting and Corrective Actions System PA0 FRP--Facilities Requirements Plan PA0 FSD--Full Scale Development PA0 GD--General Display PA0 GFE--Government Furnished Equipment PA0 GPC--General Purpose Computer PA0 GPS--Geographic Positioning System PA0 I&Q--In Phase and Quadrature Radar Data PA0 ICD--Interface Control Document PA0 ICS--Intercom Control System PA0 IFPM--In-Flight Performance Monitor PA0 IJSS--Integrated JSTARS Simulation PA0 ILS--Integrated Logistics System PA0 IMS--Inertial Measurement System PA0 INU--Inertial Measurement Unit PA0 IOU--Input/Output Unit (for the HAWK/32) PA0 IPB--Illustrated Parts Breakdown PA0 ISR--Interrupt Service Routine PA0 ITF--Integration and Test Facility PA0 ITQ--Invitation to Quote PA0 J/B--Junction Box PA0 JBIC--Junction Box Interface Card PA0 JDB--JTIDS Data Bus (a MIL-STD-1553B bus) PA0 JTIDS--Joint Tactical Information Distribution System PA0 LAN--Local Area Network PA0 LCC--Life Cycle Cost PA0 LED--Light Emitting Diode PA0 LRU--Line Replaceable Unit PA0 LSA--Logistics Support Analysis PA0 LSAR--Logistics Support Analysis Report PA0 LSE--Language Sensitive Editor PA0 MADS--Militarized Advanced Disk System PA0 MAF--Mission Archive File PA0 .mu.AFP--Micro Advanced Flexible Processor PA0 MILVAX--Militarized VAX computer, proprietary name for computer product PA0 MSM--Memory Support Module PA0 MSU--Mission Support Utilities PA0 MTBF--Mean Time Between Failures PA0 MTI--Moving Target Indication PA0 MVCF-860--Militarized VAX Computer Family Model 860, manufactured by Raytheon PA0 NCP--Network Control Program PA0 NDDL--Network Display and Development Lab PA0 NDI--Non-Developmental Item PA0 NHIT--Network Heat Interface Test PA0 NTDS--Naval Tactical Data System PA0 OCO--Operations and Control Operations PA0 OCTL--Operations and Control Test Lab PA0 ORT--Operational Readiness Test PA0 OWS--Operator Work Station PA0 PCA--Physical Configuration Audit PA0 PCM--Power Control Module PA0 PCU--Pulse Compression Unit PA0 PDIR--Price and Delivery Information Request PA0 PDL--Processor Development Lab PA0 PDR--Preliminary Design Review PA0 PDU--Program Development Unit PA0 PIDS--Prime Item Development Specification PA0 PMB--Processor Memory Bus PA0 PME--Prime Mission Equipment PA0 PMR--Program Management Review PA0 PN--Part Number PA0 PQT--Preliminary Qualification Test PA0 PS--Programmable Signal PA0 PSE--Peculiar Support Equipment PA0 PSP--Programmable Signal Processor PA0 RADB--Requirements Allocation Database PA0 RAM--Random Access Memory PA0 RCU--Radar Control Unit PA0 RDO--Radar Data Operations PA0 RDP--Radar Data Processor PA0 RDS--Radar Data Stimulator PA0 RDU--Radar Data Unit PA0 REBNA--Raytheon Ethernet Bus-interconnect Network Adapter PA0 RL--Runtime Library PA0 RMB/32--Synchronous/Asynchronous Communications Card PA0 RMS--Record Management Services PA0 RSB--Radar Subsystem Bus (a MIL-STD-1553B bus) PA0 RTL--Radar Test Lab PA0 RTMM--Removable Transportable Memory Modules PA0 SAR--Synthetic Aperture Radar PA0 SASS--Scenario and Simulation System PA0 SCA--Source Code Analyzer PA0 SCDL--Surveillance and Control Data Link PA0 SCM--Software Configuration Management PA0 SCP--Simulation Control Program PA0 SCR--Seller Change Request PA0 SCSI--Small Computer Systems Interface PA0 SDF--Software Development Facility PA0 SDS--Self Defense Suite PA0 SDU--Software Development Unit PA0 SEF--Scenario Execution Function PA0 SERD--Support Equipment Recommendation Data PA0 SGF--Scenario Generation Function PA0 SID--System Integration and Development Facility PA0 SIT--Software Integration Test PA0 SLPV--System Level Performance Verification PA0 SMD--Storage Module Device PA0 SMP--Symmetric Multiprocessing PA0 SOW--Statement of Work PA0 SPC--Signal Processing Controller PA0 SPM--System Performance Monitor PA0 SPTE--System Page Table Entries PA0 SQA--Software Quality Assurance PA0 SRD--Seller Requirements Document PA0 SRU--Shop Replaceable Unit PA0 SSU--System Support Utilities PA0 STDI--Standard Interface PA0 STL--System Test Lab PA0 SYD--System Diagnostics PA0 TBD--To Be Determined PA0 TBS--To Be Supplied PA0 TIDB--Test and Integration Data Base PA0 TIM--Technical Interchange Meeting PA0 TJ--Terminal Junction PA0 TO--Technical Order PA0 TOD--Time-of-Day PA0 TPU--Test Processing Utility PA0 TRD--Test Requirements Document PA0 TSG--Threat Scenario Generator PA0 UNIX--An operating System PA0 VAX--DEC family of compatible computers PA0 VLSI--Very Large Scale Integration PA0 VMS--Virtual Management System (DEC operating system) PA0 VPC--Vector Processor Controller PA0 VPCA--VAX Performance and Coverage Analyzer PA0 VRTX--Virtual Real-Time Executive (operating system) PA0 VSS--VAX System Support PA0 VUP--VAX Unit of Processing PA0 XMAU--External Memory Access Unit
The principal object of the invention is to provide a JSTARS which provides sufficient flexibility and growth to present future functional and technical enhancements to be incorporated with minimal impact.
An object of the invention is to provide a JSTARS which accommodates planned functional enhancements and provides the flexibility necessary to address the projected functional enhancements of the system.
Another object of the invention is to provide a JSTARS having the processing path capability necessary to permit future enhancements.
Still another object of the invention is to provide a JSTARS having improved overall system reliability and maintainability.
Yet another object of the invention is to provide a JSTARS having a decreased life cycle cost.
An object of the invention is to provide a JSTARS having great system flexibility.
Another object of the invention is to provide a JSTARS having minimized aircraft impacts.
Still another object of the invention is to provide a JSTARS having a decreased number of militarized computers, thereby decreasing the amount and complexity of software necessary to control and coordinate them.
Yet another object of the invention is to provide a JSTARS having minimized software development impact.
An object of the invention is to provide a JSTARS which permits baselining of the production configuration.
Another object of the invention is to provide a JSTARS having improved built-in test.
Still another object of the invention is to provide a JSTARS which requires no new PSE.
Yet another object of the invention is to provide a JSTARS which requires fewer spares.
An object of the invention is to provide a JSTARS having improved software maintenance capabilities.
Another object of the invention is to provide a JSTARS with decreased facility requirements for data module storage.
Still another object of the invention is to provide a JSTARS which is more compact than known systems.
Yet another object of the invention is to provide a JSTARS which is less complex than known systems.
An object of the invention is to provide a JSTARS which is more powerful than known systems.
Another object of the invention is to provide a JSTARS having enhanced overall maintainability through its advanced computer program via in-flight repair capability for the disk units, reduction in fault isolation time, elimination of a special card extraction tool, identical hardware for both Level-1 and Level-2 disk units and less maintenance due to higher mean time between failures of equipment and fewer line replaceable units in the system.
Still another object of the invention is to provide a JSTARS having an advanced computer program which provides the flexibility necessary to address the projected functional enhancements of the system.
The key to the architectural solution is the militarized computer.